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1.
设置半封闭开顶式人工气候室,研究大气CO2浓度升高与不同施氮肥处理相互作用对新疆滴灌棉田土壤氮含量变化的影响。在不同CO2浓度(360、540 μmol•mol-1和720 μmol•mol-1)条件下,不同施N处理(0、150、300 kg•hm-2 和450 kg•hm-2)对棉花花铃期0~20 cm和20~40 cm土壤NH+4 N、NO-3 N和全N含量变化进行测定。结果显示:相对于对照CO2 浓度处理,当CO2浓度为540 μmol•mol-1时,各施氮水平下土壤NO-3 N含量降低,且高氮处理下降低更为显著,全N含量无显著变化;土壤NH+4 N含量在N0、N150水平有小幅度增加,在N300、N450水平降低。当CO2 浓度为720 μmol•mol-1时,土壤NO-3 N、全N含量仍是降低的,但降低幅度低于CO2 540处理;而土壤NH+4 N含量表现为显著增加。每个CO2浓度处理下,随着施氮肥水平增加,土壤NH+4 N、全N含量呈增加趋势,但高N处理增加比例低于低N处理;土壤NO-3 N含量变化不大。总体比较,CO2 540 N300处理,土壤NO-3 N含量显著低于其他C、N组合。0~20 cm、20~40 cm两个土层之间,土壤中不同N素变化趋势基本一致,但0~20 cm土层土壤N养分含量变化更为明显。研究表明:大气 CO2浓度升高为540 μmol•mol-1时,在施N 300 kg•hm-2处理下,更有利于棉花对土壤N尤其是NO-3 N养分的吸收利用。  相似文献   

2.

The aim of this study was to evaluate the water and nitrogen use efficiency and some quantitative and qualitative characteristics of forage beet cultivars under the influence of different irrigation methods and nitrogen levels in two cropping years, 2017–18 and 2018–19, at Agricultural Research Station in Karaj, Iran. Experimental factors included the first factor with four irrigation methods (normal leakage, alternate furrow irrigation, fixed furrow irrigation, type (drip-strip)), the second factor was the amount of nitrogen fertilizer with three levels (150, 200 and 250?kg N ha?1) and the third factor included three forage beet cultivars (Sbsi052, Jamon and Kyros). Among irrigation treatments, alternate furrow irrigation and fixed furrow irrigation had the highest sugar content with 9.28% and 9.17%, respectively. The highest yield of digestible organic matter was obtained in leakage irrigation treatment, nitrogen fertilizer of 250?kg ha?1 and in Kyros at the rate of 19.45?t ha?1. The highest yield of root digestible dry matter, potassium, sodium and free nitrogen was observed in leakage irrigation treatment and consumption of 200?kg ha?1 nitrogen was observed in foreign cultivars. The highest crude protein was observed in alternate furrow irrigation conditions with a consumption of 200?kg ha?1 nitrogen in cultivar Sbsi052 at 13.08%. Leakage irrigation and type tape had the highest consumption efficiency and efficiency of nitrogen uptake with application of 150 and 200?kg ha?1 N, and the highest water use efficiency was also observed in leakage irrigation and type tape with application of 250?kg ha?1 N in domestic and foreign cultivars. The type irrigation method showed better quantitative and qualitative yield than the furrow irrigation methods.

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3.
喷灌条件下冬小麦最佳水肥管理模式试验研究   总被引:1,自引:0,他引:1  
为探讨喷灌条件下冬小麦水肥综合管理模式,采用二次回归正交设计方法安排试验方案,建立了作物产量与水肥关系经验公式,并提出了喷灌条件下最佳水肥管理模式。  相似文献   

4.
1990年-1995年在河南省沙区进行多点肥料田间试验,采用正交旋转设计和单形重心设计,探讨冬小麦的氮肥效益与降水量,土壤有机质含量,有机肥和磷肥施用量的关系以及氮肥的施肥期结构,研究表明,冬小麦对氮肥的边际效益随施肥量增加而减小,在其它因子为中等条件时,最高产量和最大肥料经济效益的施氮量分别为268kg/hm^2和213kg/hm^2,相应产量分别为4575kg/hm和4556kg/hm62。  相似文献   

5.

To investigate the effect of different planting dates and irrigation regimes on six canola cultivars, a 2-year (2014–2016) experiment was conducted at the Seed and Plant Improvement Institute of Karaj. The experiments were conducted as the factorial split-plot in a randomized complete block design including six canola cultivars (Gabriella, Brutus, Triangle, Marathon, Danube, and Natali), two irrigation regimes (fully irrigated and irrigation termination at the flowering stage) and two planting dates (October 1 and November 1). The results showed that irrigation termination from the flowering stage prevented the supply of required material for filling the seeds and the metabolism of the seed compounds and reduced the growth period of the seed. Therefore, a reduction was observed in the content of oleic and linoleic acids and proline. Also, water deficit stress caused an increase in the glucosinolate content of the seed. The response of canola cultivars was different in terms of fatty acids, so that the Natali cultivar had higher palmitic, oleic acids, and proline content compared to the other cultivars at both planting dates. Fully irrigated treatment and planting date of October 1 produced the highest amount of seed and oil yield (4659 and 2073?kg ha?1), palmitic acid (5.5%), and proline (22.7?μmol/g) content, and the lowest glucosinolate content (13.2?mg/g). Generally, the Natali cultivar and planting date of October 1 and the fully irrigated regime are highly recommended in the studied area regarding qualitative traits and yield of canola.

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6.
基于棉田膜下滴灌技术的管网设施,开展了随水滴施高水溶性碳素肥料,以提高棉田冠层CO2浓度及其效应研究。通过设置不同的碳氮施肥组合处理,对棉花冠层CO2浓度、光合速率及产量构成等进行测定分析。结果表明:随水滴施高水溶性碳素肥料(水不溶物〈1%)能有效提高棉田冠层CO2浓度;在不同的碳氮施肥处理中,盛花期冠层CO2浓度随碳...  相似文献   

7.
测定了5种拮抗细菌处理种子对水稻恶苗病的防效和对水稻产量形成的影响。结果表明,用拮抗细菌B┐916、91┐2、31┐2、A┐2和A┐3浸种可有效地防治苗期恶苗病的发生,防效达84.55%~95.57%,其中A┐3和31┐2在成株期仍有较高的防效,分别为81.57%和79.53%。5种拮抗菌处理种子均对水稻结实有明显的促进作用,其中A┐2显著促进分蘖作用,91┐2能明显增加千粒重  相似文献   

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9.
氮肥追施模式对遮阴下棉花光合效率及产量的影响   总被引:1,自引:0,他引:1  
通过探讨果棉间作下棉花适宜的氮肥追施模式,为间作棉田合理氮肥施用提供理论依据。以中棉所49为试验材料,设置不遮阴(CK)和遮阴50%处理,每个处理3个氮肥追施模式N_1(氮肥前移)、N_2(正常追肥)、N_3(氮肥前移比例较N_1大),研究氮肥追施对遮阴膜下滴灌棉花光合特性和产量的影响。结果表明:与CK相比,遮阴50%处理下棉花叶片叶绿素含量和叶面积指数增加,净光合速率下降,伏前桃比例减少,秋桃比例增加。遮阴50%处理下,氮肥追施适当前移(N_1),可提高棉花光合速率,促进光合产物的形成与积累,增加伏桃比例,显著提高了单株铃数、单铃重和皮棉产量。因此,可以考虑将氮肥适量前移(N_1),作为果棉间作下棉花提高光能利用率和产量的有效途径。  相似文献   

10.
11.

Drought stress is the main factor limiting the growth and crop yield in most regions; thus, reducing the effects of drought stress is a research priority worldwide. The aim of this experiment was to evaluate the effect of sodium nitroprusside (SNP) on physiological traits and grain yield of oilseed rape under drought stress. Two field experiments with three irrigation levels (I1: full irrigation (control), I2: irrigation cut-off at the beginning of pod development, and I3: irrigation cut-off at the beginning of grain filling) and SNP foliar applications with four levels (0, 100, 200 and 300?μM) were conducted during the 2015–2017 growing seasons. The results indicated that applying 200 and 300?μM of SNP significantly increased antioxidant enzymes, total chlorophyll, and proline at all levels of drought stress in comparison with applying zero and 100?μM of SNP. Moreover, applying SNP increased grain yield via improving the biochemical traits of the plant under stress and non-stress conditions. Comparison results of the average test of two years showed that the application of 200 and 300?μM SNP increased grain yield to 11.2 and 15.1% in control conditions, 33.6 and 36.7% in I2 and 20.9 and 40.6% in I1 compared to the control. Generally, the results indicated that applying SNP reduced the effects of water-deficit stress on oilseed rape.

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12.
浅析灌溉对作物根系及产量的影响   总被引:2,自引:0,他引:2  
李夏 《江西植保》2014,(2):188-190
结合文献资料,从作物根系的水平分布、垂直分布、硝态氮运移及产量等几个方面,概述了不同灌溉量和灌溉方式对作物的影响,分析了滴灌、渗灌等微灌技术的应用。最后,针对经济林木生产的实际现状,进行了展望:探索一种成本低、简单易操作、便于推广应用的灌溉措施更具有理论和实践意义。  相似文献   

13.
随着再生水灌溉的迅速发展,再生水灌溉对土壤环境及地下水的影响日益受到人们的关注。通过再生水灌溉田间试验,探讨了不同潜水埋深条件下,再生水灌溉对土壤中硝态氮、铵态氮及地下水中硝态氮的影响。试验结果表明:灌水后,土壤中硝态氮含量均显著增加,相同潜水埋深,灌水水平越高,土壤中硝态氮含量增加越多;灌水后,灌水水平B1不同潜水埋深地下水硝态氮分别增加11.71mg/l、15.82mg/l、15.16mg/l;灌水水平B2不同潜水埋深地下水硝态氮分别增加33.881mg/l、30.37mg/l、25.29mg/l。潜水埋深越深,地下水中硝态氮的浓度增加越小;潜水埋深越浅,地下水中硝态氮的浓度增加越大,由于淋溶和硝化作用产生的硝态氮造成浅层地下水污染的风险越大。  相似文献   

14.
为揭示滴灌不同水分调控下设施栽培葡萄产量与土壤学特性等相关指标的响应关系,在甘肃省永登县设施葡萄试验基地开展葡萄滴灌不同生育期水分调控田间灌溉试验,分析水分调控对设施栽培葡萄土壤积温、蔗糖酶和淀粉酶活性、有机碳(TOC)、微生物量碳(MBC)和微生物熵(qMB)等土壤学特性的影响,基于隶属函数综合分析明确影响葡萄产量及各项土壤生物学特性指标的最佳水分优化处理。结果表明:新梢期水分胁迫的土壤积温、土壤酶、TOC、MBC、qMB均显著(P <0. 05)高于对照;新梢期水分胁迫较对照可增产44. 6%;果实膨大期作为葡萄生长的关键阶段,此时水分胁迫对土壤淀粉酶影响不显著,但对其他土壤学特性指标具有一定的抑制作用,并且可减产9.7%;隶属函数综合分析表明,土壤生物学特性指标及产量综合隶属排名为:PS﹥FS﹥CS﹥CK﹥ES。  相似文献   

15.
为了研究不同灌溉模式下氮肥水平对水稻生物学特性及水分利用效率的影响,以两优培九为材料,设计3种不同的灌溉模式(常规灌溉、干湿交替灌溉和厢沟灌溉,分别记作W1,W2,W3)和4种不同氮肥水平(0,90,180,270 kg/hm2,分别记作F0,F1,F2,F3)的大田试验。结果表明:与W1处理相比,W2和W3处理水稻灌...  相似文献   

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17.
氮素对作物生长有着重要的作用。氮肥的施用量逐年增长,自20世纪90年代后,中国的氮盈余量保持在3.60×10~6~5.46×10~6t·a~(-1)。氮肥的利用不但决定作物的长势,同时对环境也带来了较大的影响。采用离子交换树脂法,对土壤中的硝态氮和铵态氮进行原位测定,较为准确地反映了土壤硝态氮和铵态氮的迁移、淋溶和转化等动力特性。研究表明:1埋置土壤中的离子树脂解吸液中各养分的含量均在合理的常规化学检测范围内。2在棉花生育期内,施肥和棉花生长对土壤硝态氮影响较大,施肥会显著提高土壤硝态氮的含量,而在棉花出苗80 d前后土壤硝态氮有明显亏缺。3滴灌棉田土壤铵态氮的含量较低,其时空变化较为复杂,无明显规律,作为施肥参考作用不大。  相似文献   

18.
通过田间试验初步研究采自上海市青浦区、浦东新区、嘉定区等地的籼型和偏籼型杂草稻以及采自崇明区的粳型杂草稻对水稻生长、产量构成因子和产量的影响。结果表明,在水稻营养生长期,不同籼型、偏籼型杂草稻密度对水稻基本苗、株高、单株鲜质量、分蘖数、倒二叶长、倒二叶宽均未有明显影响;而籼型和偏籼型杂草稻密度对产量构成因子有效穗数、穗长、一次枝梗数、穗粒数、千粒质量、结实率等均能产生一定影响,而粳型杂草稻只对水稻有效穗数、结实率、千粒质量等产生一定影响,实际产量等均随杂草稻密度的增加呈下降趋势。青浦区、浦东新区、嘉定区等地的籼型、偏籼型杂草稻和崇明区粳型杂草稻导致水稻产量损失50%时的密度分别为8.19、12.82、15.45、19.82株/m~2。  相似文献   

19.
滴灌随水施肥对土壤有效氮动态的影响   总被引:3,自引:1,他引:3  
通过盆栽试验,探讨2种肥料在滴灌随水施肥条件下,对土壤有效氮动态的影响。结果表明:在蕾期,不施肥处理的对照和施喷滴灌专用肥的处理在0~10cm土层的土壤有效氮均小于10~21cm土层;施美国二铵的处理各土层有效氮均无明显差异;10~21cm土层的有效氮施喷滴灌专用肥的处理高于施美国二铵的处理。在收获后期,各处理土壤有效氮从上部土层至下部土层呈下降趋势,0~5cm土层的有效氮明显高于其它土层。与蕾期相比,收获后期所有处理各土层有效氮均普遍增高。以上两时期施肥处理的有效氮均高于不施肥处理的对照,施喷滴灌专用肥处理的有效氮又高于施美国二铵处理的有效氮。充分说明,在相同氮、磷、钾条件下,施用的肥料不同,土壤中有效氮的积累不同。与美国二铵相比,喷滴灌专用肥更适用于滴灌随水施肥的肥料品种。  相似文献   

20.
施氮量对膜下滴灌棉花氮素吸收、积累及其产量的影响   总被引:4,自引:0,他引:4  
2004年在膜下滴灌条件下,研究了施氮量0,180,270,360kg/hm2对膜下滴灌棉花氮素的吸收、累积和产量及氮肥利用率的影响。结果表明:施用氮肥可以显著提高棉花的生物和经济产量及地上部分总吸氮量,但过量施用氮肥对经济产量和生物产量增产不显著,各施氮处理氮肥利用率在27.6~33.8%之间,随施氮量的增加而降低。植株中氮素含量随生育延长而降低,氮素累积总体呈增加趋势,施氮量对棉花氮素吸收有显著影响,同一生育时期,氮素含量和累积量都随着施氮量增加而提高。本试验条件下,棉花的合理施氮量应控制在270 kg/hm2左右。  相似文献   

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